This invention relates to alkanolamine, alkylamine and aminoalkylketo derivatives having useful therapeutic properties. It is particularly concerned with novel substituted 1-phenyl-2-alkylaminoalkanols, 1-phenyl-2-alkylaminoalkanes and .alpha.-aminoalkyl phenyl ketones which are .beta.-agonists, i.e. stimulate the .beta.-adrenergic receptors. In particular, these compounds increase the force of myocardial contraction, and are useful in the curative or prophylactic treatment of cardiac conditions such as congestive heart failure. By virtue of their .beta.-receptor stimulating properties these compounds are also useful in the treatment of obstructive airways disease and peripheral vascular disease.